stem-ed scotland · 2020. 6. 24. · understand, and form a mental model of, the topic on the basis...

Building a New Educational Frameworkto Address the STEM Skills GapA fundamental review from a 21st century perspective

STEM-ED Scotland

AnnexesA: Science storylines supporting entry to study in higher educationB: The teaching Units

Report by STEM-ED ScotlandDecember 2010

STEM-ED Scotland is a partnership aiming to champion world class education in Science, Technology, Engineering and Mathematics

Acknowledgements

The work of this report was carried out by STEM-ED Scotland, and the authors would like to thank our funders, the Scottish Funding Council, for providing the support that made this project possible. Thanks are due to the University of Glasgow, who kindly allow us the use of our office space, and to our STEM-ED Scotland partners and others for helpful discussions and comments at various meetings. Particular thanks are due to Robert Risk, who helped greatly with the development of Units which were of a biological nature.

Authors

Professor John Coggins Pro Vice Principal, the University of Glasgow Professor Alan Roach STEM-ED Scotland, the University of Glasgow Dr Michael Guy STEM-ED Scotland, the University of Glasgow Moira Finlayson STEM-ED Scotland, the University of Glasgow Nigel Akam Skills Development Scotland

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Copyright © 2010 STEM-ED Scotland

Stem-Ed Scotland 12a the Square University of Glasgow Glasgow, G12 8QQ

Web: http//www.gla.ac.uk/stem

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Contents Annex A: Science storylines supporting entry to study in higher education .............................................................. 5

Physics ................................................................................................................................................ 6

Chemistry ........................................................................................................................................... 13

Biosciences ......................................................................................................................................... 16

Earth systems science ............................................................................................................................. 18

Annex B : The teaching Units ................................................................................................................. 21

Numeracy ........................................................................................................................................... 33

Atoms and molecules ............................................................................................................................. 45

Forces, motion, energy ........................................................................................................................... 53

Earth processes .................................................................................................................................... 67

Ecosystems .......................................................................................................................................... 77

Energy sustainability .............................................................................................................................. 89

Reactivity .......................................................................................................................................... 101

Electricity .......................................................................................................................................... 111

Equations and graphs ............................................................................................................................ 123

Study of a domestic appliance ................................................................................................................. 131

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Calculus ............................................................................................................................................ 143

Eukaryotic cells ................................................................................................................................... 151

Radiation ........................................................................................................................................... 161

The human organism ............................................................................................................................. 171

Investigation of a large infrastructure project .............................................................................................. 187

Statistics ........................................................................................................................................... 199

Materials ........................................................................................................................................... 209

Prosthetics ......................................................................................................................................... 219

Industrial chemical processes .................................................................................................................. 229

Commercial case studies ........................................................................................................................ 239

Information systems .............................................................................................................................. 251

The universe ....................................................................................................................................... 267

Nanotechnology ................................................................................................................................... 279

Genetics ............................................................................................................................................ 289

Analysis of a commercial application ......................................................................................................... 299

Annex A: Science storylines supporting entry to study in higher education

In approaching any new area of study or application, a good STEM practitioner will set out to understand, and form a mental model of, the topic on the basis of a conceptual picture established from previous studies of science. This conceptual picture is described here as a series of basic science storylines, presented at an appropriate depth as a basis for entry to study at higher education in Scotland, in any STEM subject.

The storylines are written descriptively. They form an appropriate mental starting point. The rigorous scientific investigation and analysis to follow require application of the appropriate levels of skills and methodologies described in Chapters 3 and 5 of the main part of this report on Building a New Educational Framework to Address the STEM Skills Gap (STEM-ED Scotland, 2010).

The storylines are listed under the discipline subject headings of Physics, Chemistry, Biosciences and Earth Systems Science. This can be a little misleading as the science disciplines do not represent separate water-tight areas of study, and conceptual strands bridge traditional subject boundaries. Several of the storylines described below could in principle have been set down under different subject headings. Nearly all of the storylines are relevant to the understanding of topics conventionally studied under more than one disciplinary banner.

Physics has a significantly longer list of distinct strands of storyline than other sciences viewed in this way: this reflects the fact that many of the ideas of other sciences are themselves couched on a basis of fundamental ideas derived from physics, as is the technology used in many experimental investigation techniques.

ANNEX A SCIENCE STORYLINES SUPPORTING ENTRY TO STUDY IN HIGHER EDUCATION 5

Physics

Mass and energy are two fundamental properties. Within classical physics these two quantities are conserved.

Matter carries mass and is built of a number of different types of atoms, each containing a small central nucleus orbited by a number of electrons (described more fully below under the Chemistry heading). The constituent protons and neutrons of atomic nuclei are themselves composed of yet more basic elementary particles.

Energy exists in various forms including kinetic, gravitational, electrostatic, electromagnetic and nuclear. Energy is carried by radiation; material substances carry chemical energy and internal energy; and energy is held by materials distorted under stress and by gases under pressure. Energy can be transferred from one form to another.

Energy involved in internal motions of molecules and atoms within substances is described as heat. In any body or ‘system’ of material left to itself (isolated from any possibility of energy transfer in or out) random collisions between constituent particles distribute the ‘heat’ energy in a way that results in ‘thermal equilibrium’, with a uniform settled temperature throughout the body or system. Temperature, for a given system, is related to the total amount of heat energy contained: at the absolute zero of temperature the very minimum possible energy would be present, and the greater the total quantity of heat energy present the higher the settled temperature would be. When bodies at different temperatures are brought into contact, heat energy will spontaneously flow from the warmer into the cooler body, till both settle at a uniform, intermediate temperature level.

A force acting on a body, unless balanced by an equal opposing force, will cause a motion of the body, through an acceleration inversely proportional to the body's mass. One universal force (on earth) is the body's own weight, due to gravitation.

Where a force on a body is (wholly or partially) resisted by an opposing force acting at a different point, the body may be distorted to some degree, producing stress forces opposing


each applied force at its point of application. Any body held at rest must have its weight force opposed by an equal and opposite force through its point(s) of support: these forces will result in local stress forces throughout the body. In fluids (at rest), stress forces at any point have to balance in all directions; such forces are described as pressure.

Where the two opposing forces are not co-linearly aligned they will exert a torque on the body which, if not countered by an equal opposing torque, will cause a rotational acceleration. Any body involved in uniform circular motion about a central point is experiencing a centripetal force towards the centre in order to cause the continuous acceleration required to keep it on its circular path rather than to move off tangentially.

The above insights can be used to analyse, track and predict the motion of bodies in terms of positions, velocities, accelerations and kinetic energy. All forces applied between bodies (‘actions’) are opposed by equal but opposite opposing forces (‘reactions’): this results in conservation of total momentum.

Materials can exist in different physical states referred to as phases. Solids, liquids and gases differ in the extent to which cohesive forces constrain independent motions of constituent molecules. In a gas, molecules move essentially independently between random collisions: a gas will fill any container it is confined to, and molecular collisions on the container walls exert a uniform outward pressure. In a liquid, molecules are held closely together but are able to move relative to one another, exchanging partners: the total volume occupied changes marginally with pressure and temperature. In a solid, molecules are generally confined in constant positions relative to one another. The phase adopted by any substance depends on the strength of intermolecular cohesive forces relative to the heat energy invested in molecular motions. All substances will be solid at a low enough temperature, but will typically pass through phase changes into liquids and then to gases as the temperature is raised.

Many solids can be more complex in internal structure, embedding local dislocations or dopant species. There are also disordered solid-like phases such as glasses. Liquids can dissolve third-party substances, and different liquids may be freely miscible. Many gases closely approach the


model behaviour of an ‘ideal gas’, with a well-defined relationship between its temperature, pressure and volume.

A number of areas in physics can be explained in terms of wave motions. Waves can be longitudinal (as in sound waves that involve pressure fluctuations when passing through air) or transverse (as in waves on the surface of water, or electromagnetic radiation). Wave motions can occur in one dimension (as along a tautly held string), in two dimensions (as on the surface of water or a drum) or in three dimensions (as for sound and radiation). The speed of propagation of a simple regular wave pattern is equal to the product of its wavelength and frequency. Waves can be reflected at rigid boundaries or fixed points, and two- and three-dimensional waves can be diffracted when passing by fixed obstacles. Waves of different wavelengths, when travelling together, ‘superimpose’ to create more complex wave shapes. Waves of a single wavelength superimposing after reflection or diffraction can produce standing waves or interference patterns. Where a wave motion passes into a different medium (as when light passes from air into glass) it is refracted, resulting in a change of direction that varies with its frequency.

Sound involves longitudinal vibrations transmitted outwards from a vibrating source through surrounding matter, be it solid, liquid or gaseous. The speed of transmission is dependent on the substance passed through and its temperature and pressure, but it is the same for all wavelengths. Audible sounds of different frequencies link to different perceived pitch of the sound as detected through the ear. Musical notes are associated with a single frequency of sound, though usually as mixed ‘harmonics’ consisting of sound waves with frequencies that are whole-number multiples of the ‘fundamental’ frequency. The term ‘ultrasound’ refers to sound at higher frequencies than the human ear drum is sensitive to.

Some materials exhibit the property of magnetism. A magnet has a north and a south pole. Magnetic forces act between different magnets, with attraction between opposite poles and repulsion between like poles. Magnetic field lines can be traced around the vicinity of the magnet, and two interacting magnets free to rotate will tend to align themselves so that each aligns along the local field line from the other. Some atoms are magnetic, and the magnetism of a body results from the combined effect of these. Atomic magnets often point in random


directions, cancelling one another throughout the solid as a whole. When exposed to an external magnet, such materials can have their atomic magnets aligned, so that the material as a whole becomes magnetized. Motions in the earth's core mean that the earth as a whole acts as a magnet.

Electrons and nuclei carry opposite electrical charges, and hence objects of any scale may carry negative or positive charge through embodying a relative excess or deficiency of electrons. Separate charges attract or repel one another through an electrostatic force described by Coulomb's law.

Moving charges travelling through a medium constitute an electric current (this may result, for instance, from a stream of electrons flowing along a cable or a stream of ions flowing through a solution). An electrical voltage is required to sustain an electric current. The voltage provides a driving force to overcome the inherent resistance of the medium, transferring the energy required to sustain the current's flow. The voltage, current and resistance can be measured in standard units, and their values are related through Ohm's law. Materials of extremely high resistance are known as electrical insulators, whilst those of relatively low resistance are described as conductors. At very low temperatures there are a number of very specific materials, known as superconductors, that have zero resistance.

Modern electronics is based on transistors which are constructed using semiconductor materials. Semiconductors have relatively low electrical conductivity and are of two types, ‘n’ and ‘p’, with different mechanisms for conducting electricity. Transistors connect these in ways that produce devices that can switch or amplify electronic signals.

Electromagnetic induction: An electric current flowing along a wire generates a magnetic field circularly oriented around the wire, and there will thus be a force between the conductor and any nearby magnet. If the wire or the magnet is free to move, this force will cause, or induce, motion, transferring energy to this motion. When electric current is flowing along two neighbouring wires the magnetism produced in both results in a magnetic force between them, which can again act to transfer electrical energy into motion of one or both wires. These energy transfer processes can act in the reverse direction, so that when a magnet, or a wire carrying a


current, moves past another wire, energy can be transferred from the motion, ‘inducing’ an electric current in the other wire.

When a current circulates around a coil the overall magnetic field produced combines to act as a magnet positioned along the axis of the coil, referred to as an electromagnet. This arrangement can lead to much stronger forces between currents carried in two different circuits, or between one circuit and a magnet. This is exploited in the design of electric motors and transformers, and to generate electricity from fuels of diverse kinds. Electric motors and generators involve rotating coils and can naturally lead to the production of electricity in alternating current (AC) form, as is standard in commercially distributed electricity.

Electromagnetic radiation involves transverse oscillations of electric and magnetic fields that travel, in a vacuum, at a universally constant high speed, ‘the speed of light’. Radiation can occur at any wavelength over a huge range, referred to as the electromagnetic spectrum. Radiation carries energy which can be transferred to or from matter by absorption or emission.

Visible light is one form of electromagnetic radiation, covering a relatively narrow range of wavelengths, which happen to be able to be absorbed by molecules in the retina of human eyes, in a way that can generate an electrical signal that is transmitted to the brain. Different wavelengths within the visible range are perceived as different colours of light, whereas white light is a mixture of all wavelengths. Several other regions of the electromagnetic spectrum are classified, by their wavelengths, variously as radiowave, microwave, infrared (IR), ultraviolet (UV) and X-rays, and each of these regions is exploited in characteristically different technological ways. Refraction and reflection can be exploited, through the use of lenses and curved mirrors, to produce magnified images, as in microscopes and telescopes. Arrangements that will generate standing waves, or ‘resonances’, at particular wavelengths can be used to tune a receiving device to selectively detect signals at a particular frequency. Through prisms or diffraction gratings, radiation carrying a range of wavelengths can be dispersed, allowing single-wavelength beams to be selected. A special emission process can be designed, which produces intense radiation of a single wavelength in a highly directional single ‘laser’ beam, an important technology underlying many modern applications.


A number of properties mentioned above, including relative positions, velocities and forces, are characterized by both a magnitude and a direction in space. These can be described as vector quantities. Vectors can be treated by standard mathematics, which describes how they can be added and how they can be ‘resolved’ into components, and which gives useful ways to calculate how interactions involving vector quantities work out (as when a force acts to alter a velocity).

The planets, asteroids and comets of the solar system orbit the much larger sun, held by the centripetal force of its gravitational attraction. The solar system is one of billions held together in the Milky Way galaxy. This galaxy is one of billions composing the universe.

The universe is believed to have been formed in the ‘Big Bang’ many billion years ago and it continues to expand rapidly. Galaxies, stars and solar systems have developed in the intervening period, and continue to develop. The motions of stars within galaxies, and planets and moons within solar systems, are governed by gravity. Stars go through a life cycle dependent on their size, and collision events are significant in the history of planets. Much of the mass of the universe is believed to be vested in ‘dark matter’ which has not been directly observed. Much energy is similarly believed to exist in the form of unobserved ‘dark energy’.

The chemical elements are created by nuclear reactions, largely in stars. Energy from nuclear reactions fuels the emission of radiation across the electromagnetic spectrum, and also highly energetic cosmic rays. Observations of these, involving various designs of telescopes, form the basis of our understanding of the universe.

Space exploration, both manned and unmanned, provides for better telescopic observations from beyond the earth's atmosphere as well as allowing experiments under zero gravity conditions, and remote sensing of conditions on the earth and other nearby bodies. Probes can be used to land on other planetary bodies to directly analyse samples, and there has been much interest in exploring evidence of possible extra-terrestrial life. Space exploration presents severe challenges in engineering and equipment design.

Non-classical physics: The physics of the last hundred years has been hugely influenced by the discovery that many of the principles of classical physics do not hold when dealing with


phenomena of either very small or very large scale. Classical physics continues to dominate non-advanced education in the subject, partly because the classical picture continues to be valid to a very high level of accuracy within its traditional domain, and also because non-classical physics in general requires much more advanced mathematics. Nonetheless it is important, by SCQF level 6, to understand some of the non-classical storylines, at an elementary and quite general level.

Whilst the spectral range and propagation of radiation is well described by the classical wave model, radiation is created, and absorbed, as individual photons. A photon carries a packet, or ‘quantum’, of energy of magnitude proportional to the wave frequency, as given by Planck's law.

The classical laws of motion become inadequate at the molecular scale and below, where the motions of electrons within atoms and molecules, and the vibrations and rotations of molecules, follow laws of quantum mechanics. One consequence of this is that there are a limited number of ‘energy states’ for these motions, characterized by discrete values of energy. Atoms and molecules have distinct allowed energy levels. In spectroscopy, when a photon of radiation is emitted or absorbed, its frequency must be such that its energy precisely matches the energy lost or gained by an atom or molecule undergoing a transition from one allowed energy level to another.

Mass and energy can in fact be interconverted in extreme processes, and in particular this is significant in nuclear reactions. A small change of mass involves a very large change in energy, as given by Einstein's relationship E = mc2. Energy-releasing (and therefore mass-consuming) nuclear reactions include radioactivity, fission of nuclei of heavy atoms, and fusion of light nuclei. Fusion involves the greatest proportional energy change, and is the dominant energy-producing process in stars during the main part of their life cycles.

For objects and observers moving at extreme speeds relative to one another, measurements of time and distance will differ. One consequence of this is the phenomenon of ‘time dilation’.

In regions subject to extremely high gravitational forces the conventional rules of geometry do not apply: space is described as ‘curved’.


Chemistry

All materials in the normal natural world are made of atoms, and different atom types characterize different chemical elements. The periodic table lists all elements in a systematic way, and position in this table correlates closely with the different properties of elements and their atoms.

Molecules are the characteristic building blocks of most materials, and each of the very many different possible molecules consists of atoms bonded together in a specific arrangement.

Atoms contain electrically charged nuclei and electrons, and the number and arrangement of the electrons provide a basis for understanding the significance of the periodic table and the structures and properties of atoms, molecules and of substances in general.

The electrons within atoms are accommodated within a shell structure; comparing atoms in a given row of the periodic table, the outer shell (valence shell) is held more tightly for elements nearer the right, leading to decreasing atomic radius and increasing electronegativity. Proceeding down a given column of the periodic table, atoms have similar outer shell electron arrangements; they gradually increase in radius and become more electropositive.

Chemical bonds result from the transfer or sharing of electrons (for ionic and covalent bonding, respectively). The number of outer shell electrons, and the number of vacancies that could potentially be filled in the outer shell, dictate the number of bonds that ordinarily can be formed. Only the most electronegative atoms can readily form negative ions (anions). On the other hand a large number of electropositive atoms (including all elements classed as metallic) can quite readily form positive ions (cations).

In most stable molecules, electrons are arranged in pairs. Most of chemistry involves the behaviour of covalently bound molecules: each covalent bond involves a pair of electrons, and unshared valence shell electrons generally occupy ‘lone pairs’ on their parent atoms. Where a covalent bond joins atoms which differ in electronegativity, the electrons will be shared unequally, resulting in polarity of the bond. Where a covalently bonded cluster of atoms includes


a strongly electronegative or a strongly electropositive atom it may achieve full electron pairing by transfer of an electron (to or from another molecule) to make a molecular ion.

The geometric shape of a multi-atom molecule can be largely understood as resulting from repulsions between different pairs of valence shell electrons.

Electrical polarity and molecular shape strongly influence the properties of substances, how the same or different molecules are arranged and held within substances, and how molecules react.

All forms of bonds involve energy: total energy is conserved, and energy in the form of heat will generally be produced or consumed in the course of reactions.

Heat energy within matter exists through internal motions of the components within molecules, and of the whole molecules themselves: the more heat energy a substance holds the higher its temperature.

The electrical charge of electrons and nuclei explains the origins of ions, and of the electrical polarity of many molecules.

Chemical reactions involve interchange and rearrangements of atoms and bonds, to form different molecules: all atoms are conserved in these processes, which result from collisions between reactant molecules.

Chemical reactions will proceed to the point of chemical equilibrium, at which point the rate at which new product molecules are being formed from collisions of reactants is balanced by the rate of the reverse reaction in which collisions of product molecules lead to the production of reactants. The equilibrium point, at any given temperature, can be quantified in terms of an equilibrium constant for the reaction. The yield of a chemical process may be significantly limited by reaching equilibrium, and also often by the occurrence of alternative, and competing, reactions.

Carbon is a unique element in the variety of molecules for which it can provide the backbone. Carbon generally forms four quite strong and stable bonds to a number of other elements. C—C


and C—H bonds are effectively non-polar. Bonds to more electronegative atoms (eg O, N, Cl) are polar covalent, and double or triple bonds between C-atoms are relatively open to reaction. The properties and reactivities of organic molecules can be rationalized and predicted in terms of functional groups present. A functional group is a characteristic local structural feature with a well-recognized susceptibility to a range of standard types of reaction. Organic compounds are often classified according to prominent functional groups (such as alkenes, alcohols, esters, amines).

It is useful to classify different types of reaction including:

(a) redox reactions (involved, for instance, in chemical cells)

(b) acid-base reactions (which, for instance, considerably influence biological processes)

(c) substitution, addition and elimination reactions

(d) polymerization reactions.

The quantities of reactant substances consumed, of product substances formed, and of energy generated or consumed can be directly related to the corresponding changes at individual molecule level: the ‘mole’ is the scaling factor that enables such calculations.

The strength of intermolecular attractions, relative to the heat energy present, determines whether a substance is in solid, liquid or gaseous form.

In solutions, dissolved substances are stabilized by attractions to molecules of the solvent, whilst motions allow different dissolved substances to collide and potentially react.

Radiation interacts with materials through individual molecules absorbing or emitting individual photons: there is a precise energy exchange in this process, characterizing transitions involving excited states of the molecule and dependent on the precise frequency of the radiation.


Biosciences

All living things obey the laws of chemistry and physics, such as those of conservation of energy and matter; the processes of life at root involve molecular reactions and interactions.

There is huge variety and diversity in the nature of living things. Similarities and differences between organisms allow them to be classified. Organisms can be assigned scientific names that aid in cataloguing biodiversity.

All living organisms are made of cells that contain and regulate assemblies of chemicals. Cells can be aggregated into tissues, tissues into organs, and organs into organ systems.

Plants capture energy from the sun in photosynthesis, a process that forms the basis of virtually all food webs. Certain bacteria, fungi and other organisms break down and recycle waste products and dead organisms.

Carbohydrates, fats, nucleic acids and proteins are large molecular chemicals essential for life.

DNA plays a central role in the structure and functioning of individual cells and whole organisms. Cell chemistry involves a complex interplay of molecular reactions and interactions, and requires input of nutrients and export of waste material. DNA defines the genes of an organism, which determine its characteristics.

The role of DNA is central in the key processes of cell division and in the reproduction of organisms. It defines the inherited characteristics of offspring. In sexual reproduction the interplay of the genes of the two parents affects the detailed individual characteristics of the offspring.

An understanding of human anatomy, physiology and biochemistry is essential for healthy living, for exercise science and for diseases to be combated medically. Various physiological systems within humans, animals and plants act to achieve homoeostasis and control, to mediate growth and development, and to defend against infection and disease.


The nervous systems in animals allow them to derive information of their surroundings through sensory organs, and to direct and control their behaviour.

Human and animal behaviour is in general adaptive. Organisms co-exist in ecosystems and depend on one another for such things as energy, nutrients, pollination and habitats.

The range of life we see today can be understood as having evolved through natural selection.

Humans have considerably altered habitats and biodiversity, and are increasingly responsible for pollution, climate change and species extinctions.

The application of knowledge gained in the biosciences can be applied in numerous ways to advance developments in agriculture, industry and medicine. Such developments require regulation to ensure that an acceptable balance is achieved of risks relative to benefits, and that any ethical issues are properly considered.


Earth systems science

The earth formed 4.5 billion years ago during the early development of the solar system. It was pulled together by gravitation with considerable release of energy. The earth cooled from its surface, where the mean temperature over recent millennia fluctuated to a small (but highly significant) degree across an effectively steady range. The earth loses energy to space by radiation, receiving broadly balancing radiated energy from the sun and a geothermal energy flow from the interior. The latter energy store is largely replenished by natural radioactivity.

Below ground the earth consists of a surface crust, composed of igneous, sedimentary and metamorphic rocks of various mineral compositions. Below this two main layers are recognized, the mantle and core, each with a distinctive composition. Temperature and pressure increase steadily with increasing depth. Circulatory motions of material in the inner earth drive volcanic action, where material from the mantle breaks through the core, and earthquakes, where extreme forces cause local fracture and movement in the crust. Large-scale volcanic action and disturbance of the crust have been caused from time to time by collisions of comets or asteroids with the earth.

The earth's surface consists of a number of tectonic plates which move slowly relative to one another, driven by new material pushed through the crust at various mid-oceanic ridges and, where plates are pushed together, by the material of one plate being driven downwards under the other plate. Pressures from the latter process are responsible for mountain building. Most volcanic and earthquake activity is in the vicinity of plate boundaries. Earthquakes result in shockwaves that travel throughout the solid earth, and observations of these have provided the principal evidence through which the internal structure of the earth has been understood.

The composition of the earth's atmosphere has evolved over the earth's history, with oxygen becoming a significant component only after the evolution of abundant photosynthetic plant life. The pressure of the atmosphere is a consequence of the weight of gas above any given level, so the pressure drops at higher levels. Owing to heat loss from ground level, the atmosphere cools with height in the lower troposphere region, allowing mixing of the air in this part of the



atmosphere, which mostly influences weather. Higher up, from the boundary with the stratosphere, the atmosphere becomes warmer at greater altitudes due to the absorption of lower-wavelength ultraviolet radiation from the sun.

Weather is driven by differences in energy gained from solar radiation in different regions of the earth's surface, which lead to convective flows in the atmosphere that are much disturbed by differential forces due to the earth's rotation, leading to the circulatory low- and high-pressure systems. Circulation of water vapour plays a large part, as it is evaporated from oceans and land (with local energy absorption) and condensed in clouds (with energy release to the local atmosphere).

Water also considerably influences climate, through ice covering colder regions reflecting much incoming solar radiation, and through major ocean currents carrying large amounts of energy between different regions.

Natural processes of the earth, including those in its biosphere, circulate materials. Natural and human-influenced cycles of the elements carbon and nitrogen are particularly vital for life on the planet.

Human activity has depended on exploiting natural resources, through mining and processing important mineral and fuel resources, and considerably changing the biosphere through, for example, felling forests, water management schemes and agriculture. These activities steadily deplete valued natural resources, and generate waste streams that have further impacts on the environment and the biosystem it supports.

The earth's environment involves extremely complex and diverse interacting processes. Modelling these and accurately predicting future trends is scientifically very demanding. Observations and conclusions from such studies must drive and inform technologies to achieve sustainability of life and civilization, and efficient use and recycling of materials.

Annex B : The teaching Units

A New Educational Framework for Progression in Science and Engineering, SCQF Level 5/6

Introduction to the STEM-ED Scotland programme

The STEM-ED Scotland programme is a skills-led framework for developing individuals’ capabilities in science, technology, engineering and mathematics. It has been designed to engage students of mixed ability and diverse interests in active participation in their learning. It takes lecturers and students beyond the standard curriculum and allows them scope to select from a content menu that develops the different discipline strands in harmony and with mutual reinforcement. It emphasizes skills development and a broad understanding of the key concepts that are required by employers and universities alike. These key conceptual strands represent the ‘big ideas of science’ — a fundamental framework of ideas which we have described fully in Chapters 4 and 5 of the main report, Building a New Educational Framework to Address the STEM Skills Gap (STEM-ED Scotland, 2010, hereafter referred to as the main STEM-ED report). A shorter version of these ideas and methodologies is given in Section 2 below. In the introductory notes for each Unit, information is provided on its storylines and also the skills it develops.

In Chapters 1 to 5 of the main STEM-ED report (mentioned above) we describe this new model of approach to STEM education at sub-degree levels, consistent with modern perspectives, and in Chapter 6 of the main STEM-ED report we give details of our implementation model. In this annex we give the detailed Unit descriptors for our exemplar course.

ANNEX B THE TEACHING UNITS 21

The design is guided by the framework approach previously outlined in Chapter 1 of the main STEM-ED report to: (a) engage interest and commitment (b) progressively and systematically strengthen skills (c) deepen understanding of the main explanatory concepts, models and storylines of the

sciences (d) develop and apply the techniques and methodologies listed in Chapter 5 (e) select and schedule a sequence of specific applications to be studied.

The Unit titles are shown in Table 1 below, and the Unit content is given in the Unit descriptors later in this Annex.

Table 1 Unit titles

Cycle 1 Cycle 2 Cycle 3 Cycle 4 Cycle 5

Numeracy Energy sustainability Calculus Statistics Information systems

Atoms and molecules Reactivity Eukaryotic cells Materials The universe

Forces, motion, energy Electricity Radiation Prosthetics Nanotechnology

Earth processes Equations and graphs The human organism Industrial chemical processes Genetics

Ecosystems Study of a domestic appliance

Investigation of a large infrastructure

project

Commercial case studies

Analysis of a commercial application


1 Structure of the Units

The programme presented here consists of 25 Units: 5 at SCQF level 5 and 20 at SCQF level 6. Each Unit has a core driver — maths, computing, sciences or engineering. The Units are numbered according to the learning cycle to which they belong, with Units in cycle 1 being at SCQF level 5 and Units in cycles 2–5 representing increasing complexity within SCQF level 6 (see Table 1, which gives an overview of the programme).

In the introductory notes for each Unit, information is provided on its storylines and also the skills it develops. Every Unit is subdivided into a number of topic areas, and Unit notes provide an outline of content, teaching notes and resources for each of these. Within each Unit, lecturers and students may choose to concentrate on particular areas of interest. In most Units it is envisaged that individual students will undertake different tasks and report back to the rest of the class, so that no student will be expected to tackle directly all of the content in a Unit. The content of the Numeracy Unit in cycle 1, however, is so basic and important for many other Units that failure to cover all aspects may put students at a disadvantage.

The national SCQF specifications, intended to apply across all areas of education, give general statements describing the different types of context in which a given skill is demonstrated, typically referring to ‘simple tasks’ at level 5, ‘more complex situations’ at level 6 and ‘contexts requiring pre-planning’ at level 7. In Chapter 3 of the main STEM-ED report we have developed our own statements to demonstrate a similar progression. Our emphasis on the matrix of skills relevant for STEM practice means that we should naturally aim to reach a higher level in the application of these skills by the end of a course at level SCQF 6, especially skills in numeracy and analytical analysis. Our course Units are designed in the light of what we believe to be achievable for students who enter appropriately qualified at the preceding level and, although Units have been classified at level 6 overall, we indicate that the hope is that in the fifth cycle of Units students have achieved a higher level of skills development than would have been the case in a more conventional type of course.


2 Key storylines and methodologies developed in Units

The following seven lists summarize the codes and brief descriptions for the key storylines and methodologies used in the Units.

PHYSICS P1 Applications in electricity and electronics

P2 Study involving radiation (including lasers)

P3 Study of a wide range of materials properties

P4 Studies of forces, motion and energy

P5 Study involving spontaneous processes

P6 Study involving non-classical physics

CHEMISTRY C1 The periodic table as a key explainer

C2 Understanding bonding and 3D structure of molecules, notably in organic/biological and materials contexts

C3 Reactions, including mechanisms and yields

C4 Solution processes, including electrochemistry and reaction equilibrium

C5 Processes involving light absorption/emission


BIOSCIENCES B1 Organization and operation of the cell, and the nature, roles and management of the key

chemicals of life

B2 Organization and systems operation of an organism; homeostasis & control; healthy living & combating disease

B3 Cell division, reproduction, heredity

B4 Ecosystems, biodiversity & interdependence; photosynthesis, waste processing, sustainability

B5 Adaptation and evolution

EARTH SYSTEMS SCIENCE G1 Study involving (human influenced) element cycle and environmental modelling

G2 Study implicating major seismic processes

G3 Study involving evolution of the earth, the solar system and the universe

G4 Study involving weather, climate and interplay with the biosphere

MATHEMATICS METHODOLOGIES M1 Exponentials and logarithms (including exp and ln)

M2 Trigonometry, coordinate geometry

M3 Vectors in two and three dimensions, components, products

M4 Basic introductory calculus

M5 Basic statistics, variability, risk assessment

M6 Key tools from numeracy, algebra, proportion and graphs


ENGINEERING METHODOLOGIES E1 Project planning and management

E2 Product design, including fitness for purpose, reliability, safety and efficiency in use, cost effectiveness and aesthetic impact

E3 Materials selection to meet required needs and to minimize costs

E4 Process control methodologies

E5 Quality methodologies, and sustainability issues

COMPUTING & INFORMATION SCIENCES METHODOLOGIES CI1 Roots of computer science in numeracy: using symbols for quantities

CI2 The concept of information: classes of information

CI3 Solution specification for a general problem — algorithms

CI4 Basic introduction to programming (using a simple high-level language)

CI5 General ideas of how digital computers store, input, transform and output information

CI6 Analysing design issues in a range of applications (from in-built control devices in appliances to large scientific and technological information processing systems)


3 Mapping skills and concept development, and connections

Within the Unit notes, clear guidance is provided on which other Units provide useful prior knowledge and which will provide application, consolidation or extension. These links illustrate the real links between subjects that have historically been regarded as discrete and taught accordingly, and so allow the student to understand STEM education as a coherent whole as well as providing new routes to develop generic problem-solving skills. To facilitate such links, each Unit has three tables:

1 to give the key concepts and storylines associated with the Unit

2 to give links from the Unit to other parts of the programme

3 to show skills development within the Unit.

The level of skills is developed progressively (see below) throughout the different cycles. Table 2 shows how the skills are developed progressively throughout the Units (from SCQF level 5 to level 7) and Table 3 shows the storylines covered in the different Units. The column headings (1a etc) of Tables 2 and 3 link to the Unit titles (Table 1), with the number relating to the cycle (1 first cycle, 2 second cycle, etc) and the letter relating to the rows of Table 1 (a is the first row, b the second row, etc). For example, 1a is the Numeracy Unit and 5d is the Genetics Unit. The row headings of Table 2 (S1—S9) refer to the skills described in Chapter 3 of the main STEM-ED report (also given in the skills development table for each teaching Unit in this Annex). The row headings of Table 3 (P1—P6, C1—C5, etc) refer to the storylines and methodologies mentioned in Chapters 4 and 5 of the main STEM-ED report (also listed above in Section 2 of this Annex).

Enquiry-based learning develops important transferable skills and enables students to gain experience in facing the types of problems encountered by practising engineers and scientists. Independent learning is an important skill for any student to develop and is recommended for a significant part of most Units. Useful resources for this purpose, including websites, are given where appropriate. Wikipedia and similar generic web-based resources are helpful but students


should be cautioned about content that has not been subjected to any kind of review process before publication.

The assessment criteria are given for each Unit. The final Unit, Analysis of a commercial application, brings together a lot of the work done in previous Units, and its assessment will play an important role in the overall grade attained for the course.

4 The Units at SCQF levels 5 and 6

A brief summary of the content of each Unit has already been given in Chapter 6 of the main report, Building a New Educational Framework to Address the STEM Skills Gap (STEM-ED Scotland, 2010), and the detailed Units are given in this Annex. The Units have been given in five cycles; each cycle builds on the skills and knowledge gained in the previous cycle. The order or way in which Units are tackled in a given cycle is immaterial: they can be run simultaneously or in any other suitable way. At the end of each cycle there will be time allocated to review progress, to reflect on what has been learned, to look at how skills are being developed and to set future targets.

The content of the Units is not meant to be too prescriptive, and much of the work is project based. The descriptors do not say how Units should be delivered but they contain ideas and examples of possible projects. It will be up to the lecturer to decide on the most appropriate approach for a particular class.

5 Engineering as a discipline

In Chapter 5 of the main STEM-ED report, entitled ‘Important tools, methodologies and practices in STEM subjects’, under the heading ‘Engineering technology’ we broached the subject of


student awareness of engineering as a discipline. A brief outline and some useful resources for communicating what an engineer is and does were given; this has been repeated below so that it can be read in conjunction with relevant Units.

What is engineering?

The following description is quoted from the website ‘What is Engineering?’ at http://cnx.org/content/m13680/latest/

Engineering is the practical application of science and mathematics to solve problems, and it is everywhere in the world around you. From the start to the end of each day, engineering technologies improve the ways that we communicate, work, travel, stay healthy and entertain ourselves.

Engineers influence every aspect of modern life and it’s likely that today you will have already relied on the expertise of one or more engineers. Perhaps you woke to a DAB clock radio, or used a train or a bus? Maybe you have listened to an iPod? Or watched television? Did you wash your hair today? Do you have a mobile phone in your pocket or trainers on your feet? These have all been designed, developed and manufactured by engineers.

Engineers are problem-solvers who want to make things work more efficiently and quickly, and less expensively. From computer chips and satellites to medical devices and renewable energy technologies, engineering makes our modern life possible.

The above website gives further information and also discusses the difference between science and engineering.

There are different engineering disciplines, and engineers can work in many different environments. For more information about this, see http://www.enginuity.org.uk/what_is_engineering.cfm

A useful video clip entitled ‘Is engineering right for me?’ from the University of Buffalo in the USA can be found at http://www.youtube.com/watch?v=vj-H_Mbfvu4


http://cnx.org/content/m13680/latest/http://www.enginuity.org.uk/what_is_engineering.cfmhttp://www.youtube.com/watch?v=vj-H_Mbfvu4

It may also be helpful to know that there are three nationally (and internationally) recognized professional levels that can be worked towards: Engineering Technician (Eng Tech), Incorporated Engineer (IEng) and Chartered Engineer (CEng). Each of these levels can be achieved by various routes of study — going to university to study an engineering course is just one of the many options available. To find out more, see the ‘Enginuity’ website at: http://www.enginuity.org.uk/routes_into_engineering/your_options.cfm


http://www.enginuity.org.uk/routes_into_engineering/your_options.cfm

Table 2 Skills development throughout the Units (from SCQF level 5 to level 7)

1a 1b 1c 1d 1e 2a 2b 2c 2d 2e 3a 3b 3c 3d 3e 4a 4b 4c 4d 4e 5a 5b 5c 5d 5e

S1 5 5 5 5 5 6 5 5 6 5 6 6 6 6 6 6 6 6 6 7 7 7 7 7 7

S2 5 5 5 5 5 6 5 6 5 6 6 6 6 6 6 6 6 6 7 6 7 7 7 7

S3 6 6 5 5 5 6 5 6 5 6 6 6 6 6 6 6 6 6 7 6 7

S4 5 5 6 6 6 6 6 6 6 7 6 7 7 7 7 7

S5 5 5 5 5 6 6 5 6 6 6 6 6 6 6 6 6 7 6 6 7

S6 5 5 5 5 5 6 6 6 6 7 7 7

S7 5 5 5 6 5 7 6 6 6 6 6 6 7 7 7 7

S8 5 5 6 5 6 6 6 6 6 6 6 6 7 7 7

S9 5 5 5 6 6 7 7 7

The column headings (1a etc) in Tables 2 and 3 link to the Unit titles (Table 1), with the number relating to the cycle (1 first cycle, 2 second cycle, etc) and the letter relating to the rows of Table 1 (a is the first row, b the second row, etc). For example, 1a is the Numeracy Unit and 5d is the Genetics Unit.

The row headings of Table 2 (S1—S9) refer to the skills described in Chapter 3 of the main STEM-ED report (also listed in the individual skills development tables for the teaching Units in this Annex).

The row headings of Table 3 (P1—P6, C1—C5, etc) refer to the storylines and methodologies mentioned in Chapters 4 and 5 of the main STEM-ED report (also listed above in Section 2 of this Annex). Unit 5e, Analysis of a commercial application, does not directly relate to any of the key concepts/storylines. As this is the final Unit in the programme it will draw on the concepts and storylines relevant to the area chosen for study.



Table 3 Storylines covered in the Units

Unit:

Code:

1a 1b 1c 1d 1e 2a 2b 2c 2d 2e 3a 3b 3c 3d 3e 4a 4b 4c 4d 4e 5a 5b 5c 5d 5e

P1 X X X X X X X X X X X P2 X X X X X P3 X X X X X X X X X X P4 X X X X X X X X P 5 X X X X P 6 X X X C1 X X X X X X C2 X X X X X X X X X X C3 X X X X X X X C4 X X X X X X C5 X X X X B 1 X X X X B 2 X X X X X B 3 X X X B4 X X X X X X X B 5 X X G 1 X X G 2 X X G 3 X G 4 X X X X X M 1 X X X X X M 2 X X X X M 3 X X M 4 X X X X M 5 X X X X M6 X X X X X X X X X E 1 X X X X E2 X X X X X X X E 3 X X X E 4 X X X X E 5 X X X C I1 X C I2 C I3 X C I4 X C I5 X C I6 X X

SCQF Level 5 CYCLE 1

Numeracy

Introduction to the Unit

The primary purpose of this Unit is to develop an understanding of, and provide practical experience of, handling numerical information. It is important that this Unit is approached through the practical application of number rather than just learning how to manipulate numbers as an arithmetical or algebraic discipline. The examples chosen should be selected in such a way as to allow linkages to be made with as many other Units as possible. This Unit, by using real scientific problems, allows a brief introduction to many aspects of science and engineering which will be covered in greater detail in subsequent parts of the programme. The suggested content is included as a guideline only. However, this is such a basic Unit that failure to cover all aspects may put students at a disadvantage in later parts of the programme. The overall approach should be one of using practical examples from elsewhere in the programme.

This website is a useful general resource for the Unit:

http://www.teachingideas.co.uk/maths/contents02problems.htm

NUMERACY CYCLE 1 SCQF LEVEL 5 33

http://www.teachingideas.co.uk/maths/contents02problems.htm

On completion of this Unit students should be able to:

• manipulate and use numerical data in a number of scientific and engineering contexts

• understand and use indices, exponents, scientific notation and logarithms

• rearrange equations

• plot and interpret graphs (including slope and area underneath)

• understand the concepts of significant figures and relate to measured value

• present data in various formats appropriate to end use

• use elementary geometry, trigonometry and algebra

Approaches to assessment

Assessment will be mainly carried out by report and/or presentation, which could be peer marked (to reduce lecturer workload) with some sampled cross-marking by the lecturer. It may be possible to include a written assessment, which should have plenty of optional questions in order not to disadvantage any student.


Key concepts/storylines in Numeracy

Code Key concepts and storylines developed Developed by the student being required to:

CI1 Roots of computer science in numeracy: using symbols for quantities Use elementary algebra and rearrange equations

M1 Exponents and logarithms (including exp and ln) Understand and use indices, exponents, scientific notation and logarithms

M2 Trigonometry, coordinate geometry Plot and interpret graphs, carry out elementary surveying tasks and use trigonometry to process the data collected

M6 Key tools from numeracy, algebra, proportion and graphs

Manipulate and use numerical data in a number of scientific and engineering contexts. Understand and use indices, exponents, scientific notation and logarithms. Rearrange equations. Plot and interpret graphs. Understand the concepts of significant figures and relate to precision of measurement. Present data in various formats appropriate to end use. Use elementary geometry, trigonometry and algebra


Links from Numeracy to other parts of the programme

This a fundamental Unit with links forward to almost every other Unit. If the Unit is delivered as envisaged, lecturers will select examples from later Units to illustrate the necessity for students to become competent in manipulating numerical data.


Skills development in Numeracy

(Skills and levels refer to A New Educational Framework for Progression in Science and Engineering)

Skill Working at SCQF level 5

Working at SCQF level 6


Developed in this Unit by the student being required to:

S1. Learning, study, self-organization and task planning

• Carry out at least two enquiry-based exercises

S2. Interpersonal communication and team working

• Carry out at least two enquiry-based exercises

S3. Numeracy: assessing and manipulating data and quantity

• Complete the Unit satisfactorily

S4. Critical and logical thinking

S5. Basic IT skills • Use symbols to represent quantities

S6. Handling uncertainty and variability

• Calculate experimental errors and estimate the uncertainty of measured values

S7. Experimentation and prototype construction: design and execution

S8. Scientific analysis

S9. Entrepreneurial awareness


Numeracy: summary of content, teaching notes and materials

Topic Suggested content Teaching notes and materials

SI units • length • mass • volume • conversions • prefixes • scale and

magnitude

This provides an opportunity to introduce the ideas of scale and magnitude by using unit prefixes. Use areas such as electromagnetic radiation, the atom and the solar system. A useful website: http://physics.nist.gov/cuu/Units/units.html

Numbers • decimal places • fractions • ratios • precision,

accuracy and significant figures

• direct and indirect proportions

• percentages and percentage change

• interconversion of percentages, fractions and decimal numbers

A recommended approach to this topic would be through the practical use and manipulation of number in various scientific and engineering applications such as using a calculator to determine

Xn (bits in a binary integer of length n) 1/X (parallel resistors)

√X (pendulum) eX (population growth) log10X (pH and decibels) logeX (bacterial counts vs time) percentage yield (mainly organic synthesis) ratio predictions in Mendelian inheritance

This could be supported by practical work in the lab if time permits. There are two enquiry-based exercises which should be used if at all possible to stimulate interest and to encourage the development of team working and organization. These are the sports league fixture programme and the stadium design.


http://physics.nist.gov/cuu/Units/units.html

Topic Su gested cog ntent Teaching notes and materials

• percentage concentrations (w/w and v/v)

• area and volume (calculations, units and notations)

• calculator — standard function buttons and use

• order of precedence of arithmetic operations

Some useful websites: http://www.purplemath.com/modules/percents.htm http://www.slideshare.net/RyanWatt/math-presentation-3007769 For BODMAS see: http://mathcentral.uregina.ca/QQ/database/QQ.09.07/h/brit1.html.

Indices, exponents, scientific notation and logarithms

• definitions • positive and

negative interconversion

• addition, subtraction, multiplication, division in all forms

This important area is often neglected or not fully explained in the traditional approach through pure mathematics. The meaning and use of these concepts should be more fully understood if introduced by solving problems relating to, for example, dilutions, pH, Avogadro’s number, or population growth. Some useful websites: http://www.purplemath.com/modules/exponent.htm http://www.purplemath.com/modules/logs3.htm http://www.purplemath.com/modules/exponent3.htm

Formulae and equations

• simple linear equations

• quadratic equations

Real examples should be used with particular emphasis on the practice of using symbols to represent real numbers and the use of equations to represent relationships between quantities. The relationships used could be relatively simple mathematically, such as the gas laws, the equations of motion, V = IR, E = mc2. It may also be worth discussing the fact that the relationships represented by equations do not necessarily


http://www.purplemath.com/modules/percents.htmhttp://www.slideshare.net/RyanWatt/math-presentation-3007769http://mathcentral.uregina.ca/QQ/database/QQ.09.07/h/brit1.htmlhttp://www.purplemath.com/modules/exponent.htmhttp://www.purplemath.com/modules/logs3.htmhttp://www.purplemath.com/modules/exponent3.htm

Topic Su gested cog ntent Teaching notes and materials

• rearranging equations

• =, , ≤, ≥

hold under all conditions (eg ideal gases) as this would serve as introduction to the concept of uncertainty, which will be covered at a later stage in the programme. A useful website: http://plus.maths.org/issue29/features/quadratic/index-gifd.html

Plotting and interpretation of graphs

• scaling • gradient,

intercept and area under graph

• linear and non-linear interpretation

• rate of change • general shapes

of y = mx and y = x2

The practical approaches used here could come from the following areas: Boyle’s law Charles’s law Ideal gas law V = IR °C to °F conversion mph to km/h conversion rate of reaction activation energy bacterial growth equations of motion (eg V vs T → distance)

Students should be able plot data suggestive of a linear fit and be able to use the ‘x, y’ system of Cartesian coordinates. There should be some exercises in calculating and using gradients and areas under graphs to determine related quantities in preparation for later work on calculus. If time permits, practical work could allow students to collect some of their own data. If time is short then experimental data could be supplied to students. A useful website: http://www.fsmq.org/data//files/amwusareasi-9656.pdf


http://plus.maths.org/issue29/features/quadratic/index-gifd.htmlhttp://www.fsmq.org/data//files/amwusareasi-9656.pdf

Topic Su gested g content Teaching notes and materials

Presentation of data

• tables • graphs • bar charts • histograms • pie charts • scattergrams

Sets of experimental data should be given to students for presentation using one or more methods. This will provide an opportunity to introduce students to the display options available with Microsoft Excel. Some useful websites: http://www.qaproject.org/methods/resstattools.html http://www.qaproject.org/methods/reshistorgram.html http://gsociology.icaap.org/methods/presenting.htm

Data handling • mean • meaning of

significant figures

The important concept here is the understanding that there may not necessarily be a ‘right’ answer for a measurement. This can be demonstrated by using data produced by practical work as a class, to illustrate the variations in measured values and then showing that, as more values are added to obtain a mean, the result approaches an ideal value. Measurements could be made as follows: simple titration, height and weight measurements of students, measurement of respiration rates; enzyme activity reaction rates could also be used. Some useful websites: http://www.bbc.co.uk/schools/gcsebitesize/maths/data/ http://www.bbc.co.uk/skillswise/numbers/handlingdata/

Errors and precision

• precision of data collected relating to type of equipment used to collect data and its suitability for purpose (calculations should reflect data reliability)

Students often quote results to many decimal places as a result of calculator use. It should be shown that the number of significant figures is related to the precision of the measuring instrument using simple comparisons between, for example, measurement using a ruler and a micrometer or a measuring cylinder and a burette. This offers a useful opportunity for practical work. A simple approach for calculating errors: eg error = +/-√(a2 + b2 + c2), could be introduced to determine the error in a simple titration.


http://www.qaproject.org/methods/resstattools.htmlhttp://www.qaproject.org/methods/reshistorgram.htmlhttp://gsociology.icaap.org/methods/presenting.htmhttp://www.bbc.co.uk/schools/gcsebitesize/maths/data/http://www.bbc.co.uk/skillswise/numbers/handlingdata/

Topic Su gested content g Teaching notes and materials

• errors (random, systematic, relative, absolute)

• use of ± to represent absolute error

• use of estimation as a guide to accuracy

• effect of rounding off in the middle of a calculation

Some useful websites: http://mtsu32.mtsu.edu:11009/Graphing_Guides/Excel_Guide_Std_Error.htm www.radford.edu/~biol-web/stats/standerr_explanation.doc http://www.fordhamprep.org/gcurran/sho/sho/lessons/lesson28.htm

Geometry • angles and shapes

Use of angles to define basic shapes, eg triangle, square, hexagon, tetrahedron. The importance of angles and shapes within the overall programme should be emphasized with a mention of VSEPR (valence shell electron pair repulsion theory) and molecular shape, isomers, lock and key approach to drug design, and the helical shape of DNA. Some useful websites: http://www.chemistry-drills.com/VSEPR.php http://www2.chemistry.msu.edu/~reusch/VirtTxtJml/intro3.htm http://www.bbc.co.uk/schools/ks2bitesize/maths/shape_space/shapes/read1.shtml

Trigonometric ratios

• sine • cosine • tangent • Pythagoras

The functions sin, tan and cos should be related to the sides of a right-angled triangle and Cartesian coordinates, and be introduced through practical work relating to surveying problems (eg calculating the height of a tree). Mention should be made of the use of trigonometric units to describe periodic functions.


http://mtsu32.mtsu.edu:11009/Graphing_Guides/Excel_Guide_Std_Error.htmhttp://www.radford.edu/%7Ebiol-web/stats/standerr_explanation.dochttp://www.fordhamprep.org/gcurran/sho/sho/lessons/lesson28.htmhttp://www.chemistry-drills.com/VSEPR.phphttp://www2.chemistry.msu.edu/%7Ereusch/VirtTxtJml/intro3.htmhttp://www.bbc.co.uk/schools/ks2bitesize/maths/shape_space/shapes/read1.shtml


Some useful websites: http://www.slideshare.net/RyanWatt/math-presentation-3007769 http://www.gcse.com/maths/trigonometry.htm

Algebra • solving for unknowns

• equations (simultaneous, linear and quadratic)

• factorization • manipulation of

fractional expressions and equations

The use of algebra in solving practical scientific problems should be used as the basic approach, with links to other parts of the programme. A particular weakness with the traditional approach is the inability of many students to cross-multiply and rearrange equations. There are a substantial number of equations within the programme which could be introduced here and used as examples with which to work. Simultaneous equations could, for instance, use examples from the method of calculating equilibrium constants from concentrations. Some useful websites: https://www.bbc.co.uk/schools/ks3bitesize/maths/algebra/ http://www.gcse.com/maths/algebra.htm http://www.gcse.com/maths/factorising.htm https://camtools.cam.ac.uk/access/content/group/6041b37a-7fa4-4a47-808b-b20db3a36122/Module%203/Textbook%20pdf_s/3A3printableversion.pdf https://camtools.cam.ac.uk/access/content/group/6041b37a-7fa4-4a47-808b-b20db3a36122/Module%203/Textbook%20pdf_s/3A3printableversion.pdf


http://www.slideshare.net/RyanWatt/math-presentation-3007769http://www.gcse.com/maths/trigonometry.htmhttps://www.bbc.co.uk/schools/ks3bitesize/maths/algebra/http://www.gcse.com/maths/algebra.htmhttp://www.gcse.com/maths/factorising.htmhttps://camtools.cam.ac.uk/access/content/group/6041b37a-7fa4-4a47-808b-b20db3a36122/Module%203/Textbook%20pdf_s/3A3printableversion.pdfhttps://camtools.cam.ac.uk/access/content/group/6041b37a-7fa4-4a47-808b-b20db3a36122/Module%203/Textbook%20pdf_s/3A3printableversion.pdfhttps://camtools.cam.ac.uk/access/content/group/6041b37a-7fa4-4a47-808b-b20db3a36122/Module%203/Textbook%20pdf_s/3A3printableversion.pdfhttps://camtools.cam.ac.uk/access/content/group/6041b37a-7fa4-4a47-808b-b20db3a36122/Module%203/Textbook%20pdf_s/3A3printableversion.pdf

SCQF Level 5 CYCLE 1

Atoms and molecules

Introduction to the Unit

The primary purpose of this Unit is to develop an understanding of atomic and electronic structure and relate this to the properties of the elements and their position in the periodic table, chemical bonding and reactions in solution.

Students should be encouraged to research material for themselves and also to work in groups. A modified problem-based learning approach could be used for most of this Unit.

On completion of this Unit students should be able to:

• relate atomic and electronic structure to the properties of elements • relate the shapes, bonding and properties of chemical compounds to electronic structure • understand the factors involved in chemical reactions • understand the nature of reactions in solution

Approaches to assessment

Assessment could mainly be by satisfactory completion of worksheets, production of laboratory reports and written reports on aspects of bonding, the periodic table and solution chemistry. Worksheets could involve mainly calculations on energy levels in atoms, equations, yields and molarity, the mole, Avogadro’s number and pH.

ATOMS AND MOLECULES CYCLE 1 SCQF LEVEL 5 45

Key concepts/storylines in Atoms and molecules

Code Key concepts and storylines developed Developed by the student being required to:

C1 The periodic table as a key explainer Relate chemical properties of elements to their atomic and electronic structure

C2 Understanding bonding and 3D structures of molecules, notably in organic/biological and materials contexts

Relate bonding type and molecular shape to electronic structure and deduce the properties of compounds by bond type

C4 Solution processes, including electrochemistry and reaction equilibrium Investigate acid-base, redox and other chemical reactions

M6 Key tools from numeracy, algebra, proportion and graphs Manipulate equations and perform numerical and algebraic tasks


Links from Atoms and molecules to other parts of the programme

Links to other Units Topics involved

Links back to Numeracy

Atomic structure: powers of 10 and numerical calculations in energy level calculations Chemical reactions: calculations involving yields, amounts, the mole and Avogadro’s number Reactions in solution: calculations on concentration of solutions and pH

Links forward to Reactivity Chemical compounds: work in this Unit is further progressed in Reactivity, where bonding theories are advanced, organic reactions discussed and different types of polymers dealt with

Links forward to Materials The introduction to chemical compounds in this Unit is advanced in Materials to include alloys, smart materials and further types of polymers

Links forward to Eukaryotic cells Significance of hydrogen bonding in nature and the importance of pH in enzyme activity, chemical structure of lipids, etc

Links forward to Equations and graphs pH plots and bond angles

Links forward to Radiation Interaction of radiation with matter: functional groups in organic chemistry

Links forward to Statistics Laboratory quantitative measurements

Links forward to Industrial chemical processes Enthalpy changes: writing chemical equations Chemical equilibrium: writing acid-base and redox equations

Links forward to Nanotechnology Properties of nanomaterials: Carbon allotropes and hybridization of carbon


Skills development in Atoms and molecules

(Skills and levels refer to A New Educational Framework for Progression in Science and Engineering)

Skill Working at SCQF level 5



Developed in this Unit by the student being required to:

S1. Learning, study, self-organization and task planning

• Plan an experiment and carry through all steps successfully

S2. Interpersonal communication and team working

• Work as part of a team on lab and search projects

S3. Numeracy: assessing and manipulating data and quantity

• Collect and process lab data • Calculate energy levels, concentrations of solutions

and pH, perform calculations involving equations

S4. Critical and logical thinking • Design an experiment and analyse results • Draw conclusions from a project

S5. Basic IT skills • Produce lab reports, search the web for information

S6. Handling uncertainty and variability

• Begin to look at experimental errors and uncertainty of results

S7. Experimentation and prototype construction: design and execution

• Design and perform a lab experiment

S8. Scientific analysis • Analyse experimental results

S9. Entrepreneurial awareness


Atoms and molecules: summary of content, teaching notes and materials


Atomic and electronic structure

• elements in the periodic table • atomic structure, atomic number,

atomic mass and chemical symbols

• the periodic table and trends in properties

• electronic structure, electron shells and sub shells (n, l and m); Aufbau principle and Hund's rule

• basic trends in the periodic table related to electronic structure

• use of the periodic table in understanding some physical and chemical properties of the elements, including ionization energy

• introduction to energy states and absorption/emission of radiation; flame tests and simple spectra of elements

• calculations relating to energy levels and line spectra

A modified problem-based learning approach could be used, with students working alone or in groups. This topic could be approached with practical work: flame tests of common elements using appropriate salts such as sodium, potassium, calcium, barium, strontium, copper, etc. Flames could then be looked at using a spectroscope to identify lines. (Examples of spectra could also be obtained from the web.) These experiments could then be used to reason out the electronic structure of the atom, and perhaps the energy levels could be calculated from the spectral lines — although this may be left until a later Unit. The Rainbow Fire in Science Buddies website http://www.sciencebuddies.org/science-fair-projects/project_ideas/Phys_p058.shtml?fave=no&isb=cmlkOjQwMjY4MTYsc2lkOjEscDoxLGlhOkNoZW0&from=TSW gives the experiment in project form and asks students to do research to understand a list of terms and concepts. Using Google, various interactive periodic tables can be obtained with a wealth of information. These can be used to discuss trends and properties, with students finding out the information required. Trends in the periodic table are also given in the creative chemistry website http://creativechemistry.org.uk


http://www.sciencebuddies.org/science-fair-projects/project_ideas/Phys_p058.shtml?fave=no&isb=cmlkOjQwMjY4MTYsc2lkOjEscDoxLGlhOkNoZW0&from=TSWhttp://www.sciencebuddies.org/science-fair-projects/project_ideas/Phys_p058.shtml?fave=no&isb=cmlkOjQwMjY4MTYsc2lkOjEscDoxLGlhOkNoZW0&from=TSWhttp://www.sciencebuddies.org/science-fair-projects/project_ideas/Phys_p058.shtml?fave=no&isb=cmlkOjQwMjY4MTYsc2lkOjEscDoxLGlhOkNoZW0&from=TSWhttp://creativechemistry.org.uk/


Some useful websites: Interactive periodic table at: http://chemistry.about.com/library/blperiodictable.htm http://cas.sdss.org/DR6/en/proj/advanced/spectraltypes/energylevels.asp http://www.colorado.edu/physics/2000/quantumzone/lines2.html

Chemical compounds: bonding, shape and properties

• bonding (metallic, ionic, covalent including multiple, polar and coordinate bonds)

• shapes of molecules (VSEPR) • the periodic table position of

constituent elements of simple compounds in relation to the type of bonding (ionic, covalent or metallic) encountered

• introduction to hybridization using boron and beryllium compounds, methane, carbon dioxide, ammonia and water

• properties and structures of compounds and their dependence on the types of bonding involved

• diverse range of structures, their properties and function (ionic crystals, water, solvated ions, metals, macromolecules, polymers, rings & cages, bio-molecules)

A modified problem-based learning approach could be used, with students working alone or in groups. In practical work, students could look at various materials such as salt (sodium chloride), a metal, a liquid (bromine), a gas (hydrogen and nitrogen, methane), a simple polymer (polythene), examine their properties and then look at the different types of bonding. They can be asked to reason out the shapes of molecules and relate this to properties. Students can begin to look at polymers and macromolecules, at single and double bonds and the concept of oxidation states. An introduction to VSEPR (valence shell electron pair repulsion theory) should be given and the shapes of some simple molecules deduced. Some useful websites: http://www.s-cool.co.uk/alevel/chemistry/atomic-structure/the-structure-of-the-atom.html http://www.chem4kids.com/files/atom_intro.html


http://chemistry.about.com/library/blperiodictable.htmhttp://cas.sdss.org/DR6/en/proj/advanced/spectraltypes/energylevels.asphttp://cas.sdss.org/DR6/en/proj/advanced/spectraltypes/energylevels.asphttp://www.colorado.edu/physics/2000/quantumzone/lines2.htmlhttp://www.colorado.edu/physics/2000/quantumzone/lines2.htmlhttp://www.s-cool.co.uk/alevel/chemistry/atomic-structure/the-structure-of-the-atom.htmlhttp://www.s-cool.co.uk/alevel/chemistry/atomic-structure/the-structure-of-the-atom.htmlhttp://www.chem4kids.com/files/atom_intro.html


• names and formulae of the ions and associated compounds

• the concept and derivation of oxidation states of the elements when in their common compounds

Problems on formulae can be found at http://chemistry.about.com/library/weekly/bl041303a.htm Help in naming compounds can be found at http://chemistry.about.com/od/nomenclature/a/nomenclature-ionic-compounds.htm

Chemical reactions

• chemical reactions (balanced equations, conservation of matter, yield of product and scaling up reactions)

• the mole, Avogadro's number • types of reaction (precipitation,

acid-base and redox)

A modified problem-based learning approach could be used, with students working alone or in groups. Simple precipitation reactions can be demonstrated and equations drawn up, as can those of displacement reactions. There are a lot of balancing equations on the web, and there is a good web detective game called ‘Monkey Business’, which gives clues when equations are correctly balanced, at http://legacyweb.chemistry.ohio-state.edu/betha/chembal/shihome.html Another web-based project is the Avogadro’s number project, which can be used to develop an idea of scale as well as an appreciation of the mole concept. This is found at http://www.sciencecases.org/avogadro/avogadro.asp.

Reactions in solution

• water as a solvent, its polarity, and its ability to solvate molecules and ions

• hydrogen bonding and its significance in nature

• concepts of electrolytes, acid and bases, hydrogen ion concentration, pH and its measurement

Look at acids and bases by experiment — making pH paper using red cabbage, using it to measure pH of different solutions and performing a titration, at http://chemistry.about.com/od/acidsbase1/a/red-cabbage-ph-indicator.htm This can be treated as a project, with students finding out about certain key concepts such as acids, bases, logs and pH. Redox reactions could be studied by investigating how a breathalyzer works and then carrying out a titration using potassium dichromate. An experiment can be set up for demonstration as shown at:


http://chemistry.about.com/library/weekly/bl041303a.htmhttp://chemistry.about.com/od/nomenclature/a/nomenclature-ionic-compounds.htmhttp://chemistry.about.com/od/nomenclature/a/nomenclature-ionic-compounds.htmhttp://legacyweb.chemistry.ohio-state.edu/betha/chembal/shihome.htmlhttp://legacyweb.chemistry.ohio-state.edu/betha/chembal/shihome.htmlhttp://www.sciencecases.org/avogadro/avogadro.asphttp://chemistry.about.com/od/acidsbase1/a/red-cabbage-ph-indicator.htmhttp://chemistry.about.com/od/acidsbase1/a/red-cabbage-ph-indicator.htm



• acid-base reactions and neutralization

• precipitation reactions • redox reactions • concentration of solutions —

solubility and molarity • volumetric analysis involving an

acid-base titration and a redox reaction

http://electronics.howstuffworks.com/gadgets/automotive/breathalyzer3.htm and more details are given at http://www.practicalchemistry.org/experiments/advanced/redox-reactions/the-breathalyser-reaction,234,EX.html

http://elect

stem-ed scotland · 2020. 6. 24. · understand, and form a mental model of, the topic on the basis...

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